Stone met his lifelong friend and partner, Edwin Webster, while they were studying electrical engineering at the Massachusetts Institute of Technology. Upon graduation, they adhered to the advice of a professor and rather than set up shop together, Stone worked for welding and manufacturing companies while Webster took up with Kidder, Peabody, & Company. Their parents provided seed money in 1889, and they formed a consulting firm, the Massachusetts Electrical Engineering Company, whose first client was a paper mill in Maine in need of a hydroelectric plant for its power. Public utilities seemed a logical niche for the firm, and they began managing them in 1895, financing them in 1902 through an in-house securities department, and constructing them throughout the firm's history. The firm had 600 consultants house in an 8-story building by 1912, yet Stone and Webster retained adjoining desks and jointly signed their letters. Notable projects included the Los Angeles Big Creek System (1913), and by 1920 they incorporated.